2851
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 16
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 2852
- Proper Divisor Sum (Aliquot Sum)
- 1
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 2850
- Möbius Function
- -1
- Radical
- 2851
- Omega Function (Ω)
- 1
- Little Omega Function (ω)
- 1
Special
- Factorial
- no
- Catalan Number
- no
- Bell Number
- no
- Motzkin Number
- no
- Primorial
- no
Figurate Numbers
- Fibonacci Number
- no
- Triangular Number
- no
- Perfect Square
- no
- Perfect Cube
- no
- Pentagonal Number
- no
- Hexagonal Number
- no
- Lucas Number
- no
- Tetrahedral Number
- no
- Pell Number
- no
- Tribonacci Number
- no
- Pronic Number
- no
Recreational
- Happy Number
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 27
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- yes
- Composite Number
- no
- Semiprime
- no
- Squarefree Number
- yes
- Prime Power
- yes
- Prime Factorization
- no
- Twin Prime
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 414
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Coordination sequence T3 for Zeolite Code -PAR.at n=38A009857
- Number of ferrites M_{10}Y_n that repeat after 6n+50 layers.at n=10A011964
- Expansion of x/(1 - 7*x - 3*x^2).at n=5A015559
- Numbers k such that the continued fraction for sqrt(k) has period 90.at n=0A020429
- Fibonacci sequence beginning 2, 11.at n=13A022115
- Positive numbers k such that k and 2*k are anagrams in base 9 (written in base 9).at n=11A023079
- Primes that remain prime through 2 iterations of function f(x) = 6x + 1.at n=29A023256
- Primes that remain prime through 2 iterations of function f(x) = 7x + 6.at n=36A023259
- a(n) = position of n^2 + (n+1)^2 + (n+2)^2 in A000408.at n=32A024802
- Number of distinct products ijk with 0 <= i,j,k <= n.at n=35A027426
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 53.at n=4A031551
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 30 ones.at n=12A031798
- Smaller of a pair of consecutive lucky numbers with a gap of 2n.at n=12A031884
- a(n) = prime(10*n - 6).at n=41A031914
- Upper prime of a difference of 8 between consecutive primes.at n=37A031927
- Numbers k such that 117*2^k+1 is prime.at n=16A032408
- Numbers whose set of base-7 digits is {1,2}.at n=35A032928
- Positive numbers having the same set of digits in base 6 and base 7.at n=30A033170
- Primes of form x^2+35*y^2.at n=28A033224
- Primes of form x^2+87*y^2.at n=30A033256